Input: alps - process_bitmap: don't invert the Y-axis on Rushmore

Rushmore models don't have the Y-axis data in the bitmap inverted. Since
we now have 2 different Y orientations, make the Y bitmap data processing
use a forward loop like the X bitmap data processing, unifying the 2,
and invert the data later, except on Rushmore.

So far no-one has noticed this because the synaptics driver only uses the
non mt coordinates (except on clickpads, and there are no alps clickpads
using process_bitmap).

Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>